Structural channel members, commonly known as strut channel, are used ubiquitously in industrial and commercial spaces to provide mechanical support for building mechanical, electrical, and plumbing (MEP) as well as, communication cabling and other ceiling mounted building system components. Examples of these structural channel mechanical support systems include Unistrut™, Eaton B-Line™ and other similar branded and unbranded systems. Often structural channel systems are used in open ceiling structures in back rooms, hallways and basement mechanical rooms as well as other open ceiling areas of buildings. In these applications, the areas containing structural channel systems have general lighting supplied by a variety of non-specific lighting fixtures ranging from simple A Lamp type fixtures to vapor tight linear fixtures as well as many other common fixture forms. The most common fixtures used for open ceiling lighting include track lighting with spot lights, linear vapor tight fixtures and open linear fluorescent strip fixtures commonly utilizing T12-T5 linear fluorescent tubes and more recently, LED lighting sources.
The structural channel members or strut channel for these areas are selected and specified to safely support specific carrying loads for building system components. All mechanical loads attached to the structural channels increase the sizing of the structural members and associated mounting hardware. Any additional light fixture structure suspended from the strut channel structure is therefore included in these load calculations, thus reducing the carrying capacity of the overall mechanical structure. Additional load from light fixtures, electrical track light buss systems and other supporting components, such as cabling or pendant mount hardware, reduce the system mechanical load carrying capacity by tens to hundreds of pounds per section and potentially thousands of pounds over a full ceiling space. While the structural channels are specified to carry these additional loads, additional structural channel or larger, stronger structural members must be specified to accommodate the addition of lighting system loads thereby increasing costs for materials, installation time, and incidental project-related, schedule-driven costs and overhead.
Critical to the specifications of these spaces is head room or clearance for fixed and moveable equipment such as furnaces, boilers, server equipment, pumps or other common equipment found in mechanical and electrical rooms as well as physical room for workers or occupants to work in or pass through an area. Hallways in basements or industrial spaces are another common area where insufficient head room for equipment and personnel can be an issue. The head room in these spaces can be greatly reduced by the addition of lighting fixtures. Architects and designers are forced to adjust building layouts to move plumbing, electrical conduit, HVAC ducting and other building mechanical, electrical and plumbing system components to the corners of hallways, along the walls, or into other areas in order to accommodate the design space necessary for the lighting. Construction of mechanical, electrical and plumbing systems must accommodate lighting fixtures and often require routing of multiple parallel conduits, pipes or HVAC duct work. These multiple parallel routing paths result in extra bends in piping or conduit and faceting of sheet metal vents which are extremely time consuming and expensive for electrical contractors to install, negatively impacting project costs and schedules. Engineers and designers are faced with significant design challenges when determining routing for the mechanical and electrical systems while still meeting building code requirements for MEP routing, and lighting these spaces further negatively effects project schedule and costs.
Where building system components cannot be moved to accommodate the lighting fixture and still meet head space requirements, light fixtures are placed higher up in the open ceiling space resulting in significantly obstructed lighting with either poor light levels and/or non-uniform lighting, with significant shadowing from the building system components suspended below the lighting fixtures. The obstructed lighting further leads to building energy inefficiencies as higher-light level, higher-energy consumption fixtures must be specified in order to meet minimum floor level or working area light level requirements.
Due to the complexity of MEP routing, the lighting fixtures for the areas are often difficult to specify and are either left unspecified or generically specified during the building design process. The fixtures ultimately used are frequently not optimized for headroom, lighting performance, energy consumption or installation costs. Lighting fixtures used frequently provide either ineffective lighting or excess lighting resulting in poor lighting or inefficient energy designs. Insufficient uniform lighting due to shadowing or obstructed light creates dark spaces and the need for additional secondary or temporary lighting (I.e. (i.e., utility lights, head lamps or flash lights), further leading to building energy inefficiencies and increased operational costs.
Lighting fixtures added to open ceiling space are frequently painted or otherwise designed to conceal the fixture to minimize the undesired aesthetic impact on the space. Particularly in open ceiling designs, pendant and other fixture styles that hang down from the ceiling are often painted to match the ceiling or surrounding walls to try to prevent the fixture from breaking up sightlines in a space. These approaches are generally a compromise by the architect or designer and have minimal beneficial effect as the fixture structure will still block visual sightlines, impact daylighting effectiveness, and obstruct preferential views of artwork, windows, signage, emergency exits, etc., as well as block access to observe essential building electrical and mechanical systems.
The Lighting fixtures added to any space inherently add cost and time to install due to the need for additional hanging structure and electrical components necessary for the fixtures. Companies selling strut channel often provide elaborate and expensive systems for mounting lighting fixtures and routing wiring for power connection. Many of the solid-state lighting (“SSL”) fixtures used for better energy efficiency come with additional—non-standard—mounting hardware or methods. Installation time and costs are increased due to unfamiliarity with mounting the fixture by the electrical contractor or due to the need to source uncommon components necessary for mounting the light fixtures. Even traditional light fixtures require additional hangers and hardware not otherwise used by the Electrical or Mechanical Contractor in normal assembly of the ceiling space. Companies providing strut channel frequently offer a vast array of additional hangers and components for mounting suspended light fixtures, routing wiring and making power connections; all of which increase system weight, add cost and create aesthetic tradeoffs. SSL lighting fixtures and lighting fixtures in general used in open ceiling spaces tend to be inherently fragile in nature. Lens or optics are typically exposed, thin, brittle plastic and housings manufactured from thin sheet metal, plastic or aluminum extrusions that may be easily bent or damaged when handled by workers using tools and mechanical components when installing or repairing building mechanical or electrical systems, often routed in ceiling adjacent to or above the lighting fixtures. Mechanical damage to light fixtures, particularly in mechanical rooms and other industrial spaces is common, requiring full fixture or lens replacement to repair the lighting fixture and increasing fixture costs or schedule delays on projects or increasing maintenance costs for facilities.
Lighting fixtures in open ceiling food preparation areas carry a separate set of requirements in addition to having head space and fixture locations requirements, fixture access for cleaning is critical. Lighting fixtures added to support channels and frame members within food preparation spaces inherently block access for cleaning as well as create potential pockets and dead spaces above the lighting fixtures or between lighting and support structures.
Generally speaking, SSL technology has been adopted to many traditional fixtures to make improvements in energy efficiency of light fixtures used in open ceiling space applications. SSL solutions have been developed extensively for vapor tight and linear fluorescent type fixtures, again for the benefit of energy savings. SSL technology has not been as effectively applied to the problems with traditional fixtures as stated above relating to head space, loading, aesthetics and sightline obstruction and many of the solutions still use traditional or more complicated mounting systems, again adding extra costs and assembly time.
There is therefore, a general need for a lighting system providing the utility of meeting both the structural requirements of the building mechanical, electrical and plumbing systems structural support as well as meeting the general lighting requirements of the intended spaces. This need is particularly found in industrial and mechanical spaces with open ceiling construction and in open ceiling construction with low ceilings with supporting building mechanical, electrical and plumbing systems. Further, there is a general need for a lighting system with the added benefits of meeting lighting design, space aesthetics, performance and efficiency requirements intended by designers and architects without the negative tradeoffs of currently available and traditional lighting systems.